One-pot synthesis of multisubstituted quaterphenyls and cyclopropanes

Article abstract of DOI:10.1016/j.tet.2013.09.060

An efficient one-step synthetic route toward multifunctionalized quaterphenyls 3 or cyclopropanes 4 is developed from substituted chalcones 1 and sulfones 2 in good yields via a regioselective [3C+3C] or [1C+2C] annulation. The reaction features mild conditions, multisubstitution, and functional groups tolerance and is transition metal catalyst-free. The protocol provides a novel alternative to the conventional methodologies for the synthesis of quaterphenyls or cyclopropanes.

Full text of DOI:10.1016/j.tet.2013.09.060

Tetrahedron 69 (2013) 10036e10044
Contents lists available at ScienceDirect
Tetrahedron
journal homepage: www.elsevier.com/locate/tet
One-pot synthesis of multisubstituted quaterphenyls and
cyclopropanes
*
Meng-Yang Chang , Chieh-Kai Chan, Shin-Ying Lin, Ming-Hao Wu
Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung 807, Taiwan
a r t i c l e i n f o
a b s t r a c t
Article history:
Received 17 July 2013
Received in revised form 9 September 2013
Accepted 19 September 2013
Available online 25 September 2013
An efficient one-step synthetic route toward multifunctionalized quaterphenyls 3 or cyclopropanes 4 is
developed from substituted chalcones 1 and sulfones 2 in good yields via a regioselective [3Cþ3C] or
[
1Cþ2C] annulation. The reaction features mild conditions, multisubstitution, and functional groups
tolerance and is transition metal catalyst-free. The protocol provides a novel alternative to the con-
ventional methodologies for the synthesis of quaterphenyls or cyclopropanes.
Ó 2013 Elsevier Ltd. All rights reserved.
Keywords:
Quaterphenyls
Cyclopropanes
Chalcones
Cinnamyl sulfones
Electrocyclization
Intramolecular ring-closure
9
1. Introduction
unique structural properties. Therefore, enormous effort has been
invested in synthesis of functionalized cyclopropanes. Sim-
9
Polysubstituted phenyls and their analogues have occupied
a key position for the aromatic chemistry in the past decades, due
monseSmith cyclopropanation is the most often used.
1
In continuation of our investigation into the synthetic applica-
tions of substituted chalcones, a transition metal-free synthetic
route employed to create the skeleton of functionalized quater-
phenyls and cyclopropanes was investigated next. The one-pot
domino base-controlled formal [3þ3] or [1þ2] cycloaddition
route for synthesizing a series of quaterphenyls 3 or cyclopropanes
4 includes two steps: (1) 1,2- or 1,4-addition of chalcones 1 with
10
to the presence of these diversified frameworks as useful motifs in
2
,3
biological pharmaceuticals and synthetic material sciences. Al-
though a huge number of various approaches are known from the
literature, new methods for the formation of this type of poly-
11
4
phenyl skeleton attract continuous interest in the organic field.
However, transition metal-mediated reaction is the most popular
12
13,14
approach among the existing methods, especially SuzukieMiyaura
sulfones 2 and (2) intramolecular 1,6-electrocyclization
ring-closure (see Scheme 1). The expeditious ring-closure forms
N
or S 2
cross-coupling5 or transition metal catalyzed Reppe alkynes
6
15,16
[
2þ2þ2] cyclotrimerization. It should be noted that the regiose-
a six- or three-membered core structure.
lective construction of polysubstituted arenes can still be chal-
lenging via previous works because it is difficult to control specific
site-selectivity during the carbonecarbon bond formation. It usu-
O
Tol
ally results in the undesired generation of
a
mixture of
R2
R
S
R
O
Base
THF
regioisomers. Fewer methods have been utilized to solve the
regioselective issues.7 Cyclopropanes and their derivatives are
common core structures presented in a large number of biologically
active pharmaceutical agents. They could serve as versatile and
important building blocks in organic synthesis because of their
2
,8
+
or
R1
O
R2
R1
R
O
R2
R1
1
3 (for NaH)
4 (for t-BuOK)
1
2
3
4
) nucleophilic substitution
1) conjugated addition
2) intramolecular SN
ring-closure
) Julia olefination
2
) 1,6-electrocyclization
) oxidative dehydrogenation
*
Corresponding author. Tel.: þ886 7 3121101x2220; e-mail addresses: my-
Scheme 1. One-pot route of quaterphenyls 3 and cyclopropanes 4.
chang@kmu.edu.tw, mychang624@yahoo.com.tw (M.-Y. Chang).
0
040-4020/$ e see front matter Ó 2013 Elsevier Ltd. All rights reserved.
http://dx.doi.org/10.1016/j.tet.2013.09.060

M.-Y. Chang et al. / Tetrahedron 69 (2013) 10036e10044
10037
2
. Results and discussion
the equivalents of NaH (2.5 equiv and 5.0 equiv), reaction concen-
ꢀ
ꢀ
tration (10 mL and 20 mL), reaction temperature (25 C and 67 C),
and reaction time (3 h and 20 h), different product yield was ob-
served (entries 1e7). When the reaction temperature was elevated
to reflux, the yield of quaterphenyl 3a was increased and the starting
materials 1a and b was isolated in trace amounts. After screening
base-mediated reaction conditions, we found that NaH provided
To initiate the synthetic work, several chalcones 1 were prepared
in nearly quantitative yields according to our recent literature
methods from the NaOH-mediated ClaiseneSchmidt condensation
of substituted methylketones with benzaldehydes under the
10
methanolic refluxing solution. Next, one-pot synthesis of sulfones
was achieved from the allylic chlorination of commercially avail-
able cinnamyl alcohols with TsCl and Et N in CH Cl followed by
nucleophilic substitution of the resulting cinnamyl chlorides with
RSO Ph)
2
3
higher yields than other bases (DBU, Et N, DMAP). According to the
3
2
2
experimental results, we envision that NaH (2.5 equiv) is an optimal
base for increasing the yields of quaterphenyl 3a under the boiling
THF (10 mL) conditions for 3 h (entry 5).
2
Na (R¼2a, 4-MePh; 2b, 4-MeOPh; 2c, 4-FPh; 2d, 3,4-CH
2 2
O
in good yields. In an attempt to develop a practical protocol of
quaterphenyl with the structure of 1,2,4-triphenylbenzenes, a NaH-
mediated one-pot [3Cþ3C] tandem route of the starting chalcone 1a
with cinnamyl sulfone 2a in refluxing THF provided a sole quater-
phenyl 3a in a 72% yield. With the result in hand, one-pot prepara-
Based on the phenomenon, compounds 3aev were obtained by
one-pot domino methodology; they were summarized in Table 1.
The formation of skeleton 3 was confirmed through spectral anal-
1
ysis, including H NMR and HRMS spectrum. The structures of
compounds 3g and n were determined by single-crystal X-ray
17
tion of multisubstituted quaterphenyls was examined. Changing R
and R substituents of compounds 1aes or 2aec, the diversified
,2,4-triaryl-benzenes 3aev were isolated in 60e82% yields via the
1
crystallography, as shown in Figs. 1e2. Compared with the iso-
lated yields of products 3aev, it was found that skeleton 3, with
different aryl substituents (2-thiophene group, electron-
withdrawing oxygen-containing group or electron-donating flu-
oro-containing group), was distributed with moderate ranges.
Qinquephenyl 3i was also prepared from the one-pot domino re-
action of chalcone 1i with sulfone 2a via a (C3þC3) route.
2
1
above mentioned protocol.
To change the reaction conditions, we found that different yield
of quaterphenyl 3a was obtained via one-pot tandem reaction of
model chalcone 1a with sulfone 2a, as shown inTable 2. By adjusting
Table 1
a,b
Synthesis of multisubstituted quaterphenyls 3
R
O
O
NaH (2.5 equiv)
Tol
R
S
R2
R1
+
O
THF, reflux, 3 h
R2
R1
1a-s
R =, 2a, Ph; 2b, 4-MeOPh; 2c, 4-FPh
3a-v
Entry
1
Chalcones 1
Sulfones 2
Quaterphenyls 3 yield (%)
Entry
12
Chalcones 1
Sulfones 2
Quaterphenyls 3 yield (%)
O
O
2a
2a
S
Me
S
1
a
1l
Me
3
a, 72
b, 68
3l, 74
O
O
MeO
MeO
2
2a
13
2a
S
OMe
S
1
m
OMe
1
b
3
3m, 80
O
O
MeO
MeO
3
4
2a
2a
14
15
2a
2a
S
Me
S
1
c
Me
1n
3
c, 78
3n, 74
O
O
OMe
OMe
O
O
F
OMe
O
O
F
S
S
OMe
OMe
1
d
OMe
1
o
3
d, 76
3
o, 68
O
F
O
F
O
O
5
6
2a
2a
O
O
16
17
MeO
2a
2a
Me
OMe
MeO
1
e
Me
OMe
3
e, 80
1p
3
p, 60
O
OMe
O
OMe
O
O
O
O
MeO
OMe
MeO
OMe
1
f
OMe
OMe
3
f, 72
1q
3
q, 68
(continued on next page)

10038
M.-Y. Chang et al. / Tetrahedron 69 (2013) 10036e10044
Table 1 (continued )
Entry Chalcones 1
Sulfones 2
Quaterphenyls 3 yield (%)
Entry
Chalcones 1
Sulfones 2
Quaterphenyls 3 yield (%)
O
O
O
O
7
2a
O
O
18
2a
MeO
CF
1
g
1r
MeO
CF
3
g, 75
3r, 73
3s, 70
O
O
MeO
MeO
MeO
8
9
MeO
2a
2a
19
20
2a
2b
CF
OMe
CF
OMe
1s
MeO
1
hO
3
h, 78
O
OMe
OMe
OMe
OMe
Ph
Ph
OMe
1a
1
i
OMe
3
t, 82
3
i, 66
MeO
MeO
O
O
MeO
1
1
0
1
2a
21
2b
OMe
1
j
OMe
1
b
3
j, 65
3u, 70
F
O
O
F
2a
22
2c
F
S
S
1
k
1a
3
k, 72
3v, 78
a
For the best one-pot reaction conditions: (i) substituted chalcones 1aes (0.5 mmol), sulfones 2aec (0.5 mmol), NaH (60%, 50 mg, 1.25 mmol), THF (10 mL), reflux, 3 h.
The isolated quaterphenyl products 3aev were >95% pure as determined by 1H NMR analysis.
b
Table 2
a
NaH-mediated reaction of compounds 1a and 2a
ꢀ
3a, yieldb
Entry
Equiv, THF (mL), temp ( C), time (h)
1
2
3
4
5
6
7
2.5, 10, 25, 3
2.5, 10, 25, 20
5.0, 10, 25, 20
5.0, 20, 25, 20
2.5, 10, 67, 3
2.5, 10, 67, 20
5.0, 10, 67, 20
30%
50%
48%
44%
72%
67%
66%
a
The reactions were run on a 0.5 mmol scale with chalcone 1a and sulfone 2a.
The starting materials 1a and 2a were recovery (for entry 1, 50%; entry 2, 32%;
b
entry 3, 38%; entry 4, 35%; entries 5e7,<5%).
Fig. 2. X-ray structure of compound 3n.
As shown in Scheme 2, a plausible explanation for the one-pot
synthesis of compound 3a via the reaction of 1a and 2a should be
that sodium a-carbanion A1 was first generated via NaH-mediated
deprotonation of cinnamyl sulfone 2a in refluxing THF. Under
thermodynamic conditions, four possible intermediates B1eB4
should be formed by the nucleophilic substitution of intermediate
A1 with chalcone 1a. For intermediates B1 and B2, the orientation
of the oxygen anion and the sulfonyl group on the equatorial po-
sition was gauche-configured. At the stages, the oxygen anion
promoted the retro-aldol type reaction via an anti-periplanar
conformation and the equilibrium process could be generated. To
trigger Julia olefination, the orientation of the oxygen anion and the
sulfonyl group was arranged to cis-configuration. Intermediate B3
exhibited a stronger repulsion with steric hindrance than did in-
termediate B4. The gauche-configuration between the phenyl
group and the sulfonyl group (on the equatorial position) with less
steric hindrance was preferred when choosing to provide a more
stable intermediate B4. After the removal of toluenesulfonate, the
Fig. 1. X-ray structure of compound 3g.

M.-Y. Chang et al. / Tetrahedron 69 (2013) 10036e10044
10039
preferred intermediate C with a fully (E,E,E)-conjugated configu-
ration was formed. Next, quaterphenyl 3a was generated by the 1,6-
-electrocyclic disrotatory ring closure followed by sequential
oxidative dehydrogenation of the resulting intermediate D. From
the above mentioned reaction mechanism, we believe that air
Table 3 (continued )
Entry
4
Chalcones 1
Sulfones 2
Cyclopropanes 4 yield (%)
6
p
OMe
O
2a
(
molecular oxygen) plays an important oxidant role to activate the
MeO
11
1t
aromatization step during the one-pot direct transformation.
O
4
d, 80
OMe
O
5
2a
MeO
1
u
O
4
e, 62
OMe
O
MeO
6
7
2b
2d
2e
1
b
a
O
MeO
4
f, 76
O
O
1
O
O
4
g, 71
O
8
Scheme 2. A possible mechanism to compound 3a.
Me
1
a
O
4
h, 56
a
With the successful results in hand, when the base was further
changed from NaH to t-BuOK under boiling THF conditions, six
substituted cycolpropanes 4aeh with a three-membered ring
skeleton were provided in 56%e80% yields via the one-pot domino
reaction of chalcones 1a, b, f, j, l, t or u with sulfone 2a, b or 2d, e
For the best one-pot reaction conditions: (i) chalcones 1a, b, 1f, 1j, 1l, 1t, 1u
(0.5 mmol), sulfones 2a, b or 2d, e (0.5 mmol), t-BuOK (140 mg, 1.25 mmol), THF
(
10 mL), reflux, 3 h.
b
The isolated quaterphenyls 4aeh were >95% pure as determined by 1H NMR
analysis.
(
see Table 3). This is a high-yield and one-pot cascade route to the
Table 3
framework of functionalized cyclopropanes. The structural skeleton
a,b
Synthesis of Cyclopropanes 4aeh
of compound 4d was determined by single-crystal X-ray crystal-
R2
17
lography (Fig. 3).
O
t-BuOK (2.5 equiv)
O
Tol
+
R
S
R1
R2
R1
THF, reflux, 3 h
R
O
O
1
a-b, 1f, 1j, 1l, 1t, 1u 2a, R = Ph
4a-h
2
2
2
b, R = 4-MeOPh
d, R = 3,4-CH2O2Ph
e, R = Me
Entry
1
Chalcones 1
Sulfones 2
Cyclopropanes 4 yield (%)
O
O
O
O
O
OMe
2a
OMe
1
f
j
O
4
a, 70
O
OMe
2
3
2a
2a
OMe
1
O
4
b, 65
O
S
Me
S
Me
O
1
l
4
c, 73
Fig. 3. X-ray structure of compound 4d.

10040
M.-Y. Chang et al. / Tetrahedron 69 (2013) 10036e10044
Based on the results, a possible reaction mechanism for model
cyclopropanes. Further investigation regarding one-pot cascade
synthesis of multi-functionalized carbocycles will be conducted
and published in due course.
substrate 4g is shown in Scheme 3. Initially, intermediate A2 was
formed by deprotonation of sulfone 2d with t-BuOK. Intermediate
E1 or E2 should be afforded via the conjugated addition of chalcone
1
a with the resulting potassium
a
-carbanion A2. Generating the
4. Experimental section
4.1. General
intermediate E1 should not be preferred since the relative orien-
tation between the phenyl group and the sulfonyl group was cis-
configured with stronger repulsion. At another intermediate E2
stage, gauche-configuration between the phenyl group and the
sulfonyl group easily triggered the occurrence of an intramolecular
All other reagents and solvents were obtained from commercial
sources and used without further purification. Reactions were
routinely carried out under an atmosphere of dry air with magnetic
stirring. Products in organic solvents were dried with anhydrous
MgSO before concentration in vacuo. Melting points were de-
4
termined with a SMP3 melting apparatus. H and C NMR spectra
were recorded on a Varian INOVA-400 spectrometer operating at
S
N
2 ring-closure, and the three-membered ring could be cyclized
for the formation of cyclopropane skeleton. After removal of tol-
uenesulfinic potassium salt (TolSO K), compound 4g was provided.
2
1
13
During the tandem reaction procedure, the regio- and stereo-
selective formation of three contiguous chiral centers was well-
developed. So far, there are a few of literature reports to describe
the base-promoted straightforward synthesis of skeleton 4 via an
interrupted Julia reaction. Under thermal conditions, skeleton 4,
with contiguous stereogenic centers advanced an intramolecular
cascade stereospecific ring closure to three adjacent stereocenters
with the cisetrans configuration. For possible differences between
NaH-mediated 1,2-addition and t-BuOK-mediated 1,4-addition, it
should be envisioned as the nature of sodium
potassium -carbanion A2 with specific electronic effects affecting
the addition position of chalcone 1 in the formation of skeleton 3 or
4
1
200/400 and at 100 MHz, respectively. Chemical shifts (d) are re-
ported in parts per million (ppm) and the coupling constants (J) are
given in Hertz. High resolution mass spectra (HRMS) were mea-
sured with a mass spectrometer Finnigan/Thermo Quest MAT 95XL.
X-ray crystal structures were obtained with an Enraf-Nonius FR-
590 diffractometer (CAD4, Kappa CCD). Elemental analyses were
carried out with Heraeus Vario III-NCSH, Heraeus CHN-OS-Rapid
Analyzer or Elementar Vario EL III.
A representative synthetic procedure of compounds 3aev is as
follows: Sodium hydride (NaH, 60%, 50 mg, 1.25 mmol) was added
to a solution of sulfones 2aec (0.5 mmol) in THF (8 mL). A solution
of chalcones 1aes (0.5 mmol) in the THF (2 mL) was added to the
reaction mixture at rt. The reaction mixture was stirred at reflux for
3 h. The reaction mixture was cooled to rt. Water (1 mL) was added
18
a-carbanion A1 or
a
. To further investigate the origin of this regioselectivity, chalcone
f and sulfone 2a were chosen as the model materials in the re-
action of KH-mediated formal [3þ3] benzannulation or t-BuONa-
mediated formal [1þ2] cyclopropanation. We found that the cor-
responding quaterphenyl 3f (70%) or cyclopropanes 4a (65%) was
isolated as the major product, respectively. The results demon-
ꢀ
to the reaction mixture at 0 C. The solvent was concentrated under
reduced pressure. The residue was diluted with water (10 mL) and
the mixture was extracted with EtOAc (3ꢁ20 mL). The combined
organic layers were washed with brine, dried, filtered, and evapo-
rated to afford crude product. Purification on silica gel (hexanes/
EtOAc¼10/1e6/1) afforded compounds 3aev.
strated sodium a-carbanion A1 or potassium a-carbanion A2 con-
trol the shift of regioselectivity. In the other way, LDA-mediated
reaction of chalcone 1f and sulfone 2a was also examined. Qua-
terphenyl 3f (58%) along with the recovery starting materials 1f and
4
a (w15%) was observed.
ꢀ
4
.1.1. Compound (3a). Yield¼72% (110 mg); mp¼103e105 C,
(a) deprotonation
(b) conjugated addition
(c) intramolecular ring-closure
3
(recrystallized from hexanes and EtOAc); IR (CHCl ): 3054, 3032,
ꢂ1
1
þ
1
3
475, 1255, 1078, 795 cm ; HRMS (ESI, M þ1) calcd for C24
H
19
3
07.1487, found 307.1489; H NMR (400 MHz, CDCl ): d 7.70e7.65
(
m, 4H), 7.52 (d, J¼8.4 Hz,1H), 7.49e7.44 (m, 2H), 7.39e7.36 (m,1H),
13
-
BuOK
7.25e7.17 (m, 10H); C NMR (100 MHz, CDCl
140.99, 140.59, 140.36, 139.55, 131.09, 129.90 (2ꢁ), 129.87 (2ꢁ),
29.41, 128.82 (2ꢁ), 127.92 (2ꢁ), 127.89 (2ꢁ), 127.42, 127.13 (2ꢁ),
26.58, 126.52, 126.11.
3
): d 141.49, 141.11,
(
a)
(b)
K
-
1
1
ꢀ
C
TOlSO2K
c)
4.1.2. Compound (3b). Yield¼68% (131 mg); mp¼100e101
(
(recrystallized from hexanes and EtOAc); IR (CHCl
3
): 2962, 2922,
ꢂ1
þ
1
C
d
615, 1483, 1176, 1020, 750 cm ; HRMS (ESI, M þ1) calcd for
1
29
H
23O 387.1749, found 387.1755; H NMR (400 MHz, CDCl
3
):
Scheme 3. A possible mechanism to compound 4g.
8.14 (d, J¼1.2 Hz, 1H), 7.96e7.78 (m, 6H), 7.56 (d, J¼7.6 Hz, 1H),
7
.54e7.48 (m, 2H), 7.29e7.13 (m, 6H), 6.85 (dt, J¼1.2, 7.6 Hz, 1H),
13
3
. Conclusion
6.80 (dd, J¼0.8, 2.8 Hz, 1H), 6.78e6.75 (m, 1H), 3.63 (s, 3H);
C
3
NMR (100 MHz, CDCl ): d 159.10, 142.81, 141.15, 140.93, 140.22,
In summary, we have successfully presented a synthetic meth-
139.66, 137.83, 133.69, 132.72, 131.15, 129.78 (2ꢁ), 129.45, 128.96,
128.51, 128.21, 127.96 (2ꢁ), 127.65, 126.58, 126.42, 126.35, 126.01,
125.81, 125.44, 122.39, 115.28, 112.76, 55.09.
odology for multi-functionalized quaterphenyls 3 and cyclopro-
panes 4, which involves the tandem site-selective nucleophilic
substitution of substituted chalcones 1 with the carbanion of sul-
fones 2 and intramolecular 1,6-electrocyclic disrotatory annulation
4.1.3. Compound (3c). Yield¼78% (137 mg); colorless gum; IR
ꢂ1
or S
N
2 ring closure. The one-pot synthesis of quaterphenyls and
(CHCl ): 2930, 2360, 1524, 1488, 1142, 1028, 807 cm ; HRMS (ESI,
3
þ
1
cyclopropanes via base-controlled reaction conditions was in-
vestigated thoroughly. The structures of key products were con-
firmed by X-ray crystal analysis. The one-pot transition metal-free
synthetic approach begins with simple starting materials and re-
agents, and provides a potential methodology for the synthetic
research and biological activities of quaterphenyls and
M þ1) calcd for C26H23O 351.1749, found 351.1758; H NMR
(400 MHz, CDCl ):
3
d
7.69e7.63 (m, 2H), 7.59 (d, J¼8.0 Hz, 2H), 7.50
(d, J¼8.4 Hz, 1H), 7.28 (d, J¼8.0 Hz, 2H), 7.25e7.14 (m, 6H), 6.82
(ddd, J¼0.8, 1.6, 7.6 Hz, 1H), 6.77 (ddd, J¼0.8, 2.4, 8.4 Hz, 1H), 6.72
13
(dd, J¼1.6, 2.4 Hz, 1H), 3.62 (s, 3H), 2.42 (s, 3H); C NMR (100 MHz,
CDCl ):
3
d 159.06, 142.56, 141.23, 140.77, 140.30, 139.28, 137.66,

M.-Y. Chang et al. / Tetrahedron 69 (2013) 10036e10044
10041
1
37.26, 131.02, 129.77 (2ꢁ), 129.55 (2ꢁ), 129.01, 128.90, 127.91 (2ꢁ),
7.36e7.20 (m, 8H), 6.87 (s, 2H), 3.95 (s, 6H), 3.92 (s, 3H); 13C NMR
(100 MHz, CDCl ):
153.55 (2ꢁ), 141.03, 140.61, 140.57, 140.52,
126.96 (2ꢁ), 126.48, 125.99, 122.37, 115.22, 112.76, 55.06, 21.12.
3
d
1
40.40, 139.65, 139.36, 137.79, 136.60, 131.15, 130.31 (2ꢁ), 129.86
4
.1.4. Compound (3d). Yield¼76% (140 mg); colorless gum; IR
(2ꢁ), 129.24, 128.75 (2ꢁ), 128.02 (2ꢁ), 127.29, 126.95 (2ꢁ), 126.64
ꢂ1
þ
(
CHCl
for C25
CDCl ):
3
): 2896, 1604, 1473, 1158, 836 cm ; HRMS (ESI, M þ1) calcd
(3ꢁ), 126.18, 104.45 (2ꢁ), 60.98, 56.26 (2ꢁ).
1
H18FO
2
S 369.1291, found 369.1298; H NMR (400 MHz,
ꢀ
3
d
7.61 (dd, J¼2.0, 6.8 Hz, 1H), 7.60 (s, 1H), 7.50e7.35 (m, 4H),
4.1.10. Compound (3j). Yield¼65% (125 mg); mp¼137e138
C
7
6
.29e7.15 (m, 5H), 7.09e7.04 (m, 1H), 6.70 (d, J¼8.4 Hz, 1H),
(recrystallized from hexanes and EtOAc); IR (CHCl
3
): 2970, 2929,
13
ꢂ1
þ
.67e6.65 (m, 2H), 5.91 (s, 2H); C NMR (100 MHz, CDCl
3
):
d
163.23
1625, 1488, 1178, 1016, 753 cm ; HRMS (ESI, M þ1) calcd for
1
(
d, J¼244.1 Hz), 147.26, 146.44, 142.81 (d, J¼7.6 Hz), 140.93, 140.74,
40.09, 139.01 (d, J¼2.3 Hz), 135.26, 131.24, 130.28 (d, J¼8.3 Hz),
29.70 (2ꢁ), 129.27, 128.03 (2ꢁ), 126.70, 125.89, 123.44, 122.71 (d,
J¼3.0 Hz), 114.22 (d, J¼21.2 Hz), 113.96 (d, J¼21.3 Hz), 110.36, 107.99,
00.93.
C
29
H
23O 387.1749, found 387.1752; H NMR (400 MHz, CDCl
3
):
1
1
d
7.83 (d, J¼1.6 Hz, 1H), 7.80e7.77 (m, 2H), 7.74 (d, J¼2.0 Hz, 1H),
7.67e7.62 (m, 4H), 5.54 (d, J¼7.6 Hz, 1H), 7.48e7.43 (m, 2H),
13
7.23e7.17 (m, 6H), 7.02 (d, J¼8.8 Hz, 2H), 3.87 (s, 3H); C NMR
(100 MHz, CDCl ): 159.32, 141.09, 140.76, 140.08, 139.36, 139.07,
1
3
d
1
33.39, 133.09, 132.09, 131.17, 129.89 (2ꢁ), 129.32, 128.41 (2ꢁ),
4
.1.5. Compound (3e). Yield¼80% (146 mg); colorless gum; IR
128.18 (2ꢁ), 127.98 (3ꢁ), 127.59, 127.09, 126.52, 125.95, 125.84,
ꢂ1
þ
(
CHCl
calcd for C26
CDCl ):
3
): 2882, 1477, 1225, 1040, 806, 734 cm ; HRMS (ESI, M þ1)
125.79, 114.30 (2ꢁ), 55.37.
1
21 2
H O 365.1542, found 365.1550; H NMR (400 MHz,
3
d
7.61 (dd, J¼2.0, 6.8 Hz, 1H), 7.60 (s, 1H), 7.57 (d, J¼8.4 Hz,
4.1.11. Compound (3k). Yield¼72% (119 mg); colorless gum IR
ꢂ1
1
2
1
3
H), 7.47 (d, J¼8.4 Hz, 1H), 7.28e7.18 (m, 7H), 6.70 (dd, J¼0.8, 7.2 Hz,
(CHCl
3
): 2948, 1650, 1533, 1480, 1225, 1162, 847, 764 cm ; HRMS
þ
H), 6.67 (s, 1H), 6.66 (dd, J¼2.0, 7.2 Hz, 1H), 5.93 (s, 2H), 2.41 (s,
(ESI, M þ1) calcd for C22
(400 MHz, CDCl ):
7.76 (d, J¼2.0 Hz, 1H), 7.60 (dd, J¼2.0, 8.0 Hz,
H), 7.46 (d, J¼8.0 Hz,1H), 7.45e7.26 (m, 8H), 7.22 (dd, J¼1.2, 5.2 Hz,
1H), 7.10e7.05 (m, 1H), 6.90 (dd, J¼3.6, 5.2 Hz, 1H), 6.77 (dd, J¼1.2,
H16FS 331.0957, found 331.0963; H NMR
H).
3
d
1
ꢀ
4
.1.6. Compound (3f). Yield¼72% (137 mg); mp¼130e131
C
13
(
recrystallized from hexanes and EtOAc); IR (CHCl
3
): 2921, 1487,
3.6 Hz, 1H); C NMR (100 MHz, CDCl
3
):
d
163.23 (d, J¼244.1 Hz),
ꢂ1
þ
1
C
d
460, 1022, 912, 870, 841, 736 cm ; HRMS (ESI, M þ1) calcd for
142.84, 142.59, 140.90, 140.46, 139.18 (d, J¼2.3 Hz), 133.75, 131.37,
130.32 (d, J¼8.4 Hz),129.59 (2ꢁ), 129.27, 128.07 (2ꢁ), 127.15,127.09,
126.95, 126.33, 125.73, 122.73 (d, J¼3.0 Hz), 114.27 (d, J¼33.4 Hz),
114.08 (d, J¼39.4 Hz).
1
26 21 3 3
H O 381.1491, found 381.1502; H NMR (400 MHz, CDCl ):
7.60 (d, J¼8.8 Hz, 2H), 7.58 (d, J¼8.0 Hz, 2H), 7.46 (dd, J¼1.6, 6.8 Hz,
H), 7.28e7.18 (m, 5H), 7.00 (d, J¼8.0 Hz, 2H), 6.70 (dd, J¼0.8, 7.2 Hz,
H), 6.67 (s, 1H), 6.66 (dd, J¼2.0, 7.2 Hz, 1H), 5.93 (s, 2H), 3.87 (s,
1
1
3
13
ꢀ
H); C NMR (100 MHz, CDCl
3
):
d
159.30, 147.19, 146.31, 141.20,
4.1.12. Compound (3l). Yield¼74% (121 mg); mp¼115e116
C
1
1
1
40.52, 139.93, 138.89, 135.59, 133.06, 131.09, 129.74 (2ꢁ), 128.88,
28.12 (2ꢁ), 127.96 (2ꢁ), 126.49, 125.54, 123.45, 114.27 (2ꢁ), 110.41,
07.93, 100.89, 55.36.
(recrystallized from hexanes and EtOAc); IR (CHCl
3
): 3004, 2915,
ꢂ1
þ
2011,1513,1478,1253,1115, 820, 741 cm ; HRMS (ESI, M þ1) calcd
1
3
for C23H19S 327.1208, found 327.1215; H NMR (400 MHz, CDCl ):
d
7.73 (d, J¼2.0 Hz, 1H), 7.60 (dd, J¼2.0, 8.0 Hz,1H), 7.57 (d, J¼8.4 Hz,
ꢀ
4
(
1
4
1
.1.7. Compound (3g). Yield¼75% (150 mg); mp¼110e111
recrystallized from hexanes and EtOAc); IR (CHCl ): 2902, 1475,
222, 1041, 812, 739 cm ; HRMS (ESI, M þ1) calcd for C29
C
2H), 7.44 (d, J¼7.6 Hz,1H), 7.32e7.27 (m, 7H), 7.21 (dd, J¼0.8, 5.2 Hz,
3
1H), 6.89 (dd, J¼4.0, 5.2 Hz, 1H), 6.76 (dd, J¼0.8, 4.0 Hz, 1H), 2.42 (s,
ꢂ1
þ
13
H
21
O
2
3H); C NMR (100 MHz, CDCl
3
):
d
143.21, 141.16, 140.42, 139.59,
1
01.1542, found 401.1552; H NMR (400 MHz, CDCl
3
):
d
8.13 (br s,
137.47, 137.37, 133.52, 131.21, 129.65 (2ꢁ), 129.57 (2ꢁ), 129.15,
128.02 (2ꢁ), 127.03, 126.96 (2ꢁ), 126.92, 126.89, 126.25, 125.54,
21.13.
H), 7.96e7.76 (m, 6H), 7.55e7.48 (m, 3H), 7.34e7.19 (m, 6H), 6.72
13
(
br s, 2H), 5.94 (s, 2H); C NMR (100 MHz, CDCl
41.11, 140.70, 140.18, 139.60, 137.83, 135.51, 133.70, 132.72, 131.23,
29.75 (2ꢁ), 129.55, 128.50, 128.21, 128.02 (2ꢁ), 127.65, 126.61,
26.35, 126.21, 126.01, 125.79, 125.43, 123.49, 110.43, 107.98, 100.92.
Single-crystal X-ray diagram: crystal of compound 3g was grown by
slow diffusion of EtOAc into a solution of compound 3g in CH Cl to
yield colorless prisms. The compound crystallizes in the monoclinic
3
): d 147.25, 146.40,
1
1
1
4.1.13. Compound (3m). Yield¼80% (137 mg); colorless gum; IR
ꢂ1
(CHCl
3
): 2965, 2903, 1606, 1461, 1145, 996, 755 cm ; HRMS (ESI,
þ
1
M þ1) calcd for C23
H19OS 343.1157, found 343.1166; H NMR
2
2
(400 MHz, CDCl
3
):
d
7.74 (d, J¼2.0 Hz, 1H), 7.61 (d, J¼8.8 Hz, 2H),
7.73 (dd, J¼2.0, 8.0 Hz,1H), 7.43 (d, J¼8.0 Hz,1H), 7.34e7.26 (m, 5H),
ꢀ
crystal system, space group
P
1
ꢀ
21 1, a¼11.2874(12) A,
7.21 (dd, J¼1.2, 5.2 Hz, 1H), 7.01 (d, J¼8.8 Hz, 2H), 6.89 (dd, J¼3.6,
ꢀ
ꢀ
3
13
b¼5.9914(6) A, c¼15.6427(16) A, V¼1001.67(18) A , Z¼2,
5.2 Hz, 1H), 6.75 (dd, J¼1.2, 3.6 Hz, 1H), 3.87 (s, 3H); C NMR
3
ꢀ
d
calcd¼1.328 g/cm , F(000)¼420, 2
q
range 1.37e26.37 , R indices (all
3
(100 MHz, CDCl ): d 159.37, 143.23, 141.18, 140.09, 139.27, 133.51,
data) R1¼0.0470, wR2¼0.1343.
132.86, 131.22, 129.65 (2ꢁ), 128.91, 128.15 (2ꢁ), 128.02, 127.02,
126.89 (2ꢁ), 126.01, 125.53, 114.30 (2ꢁ), 114.27, 55.37.
4
.1.8. Compound (3h). Yield¼78% (154 mg); colorless gum; IR
ꢂ1
ꢀ
C
(
(
(
(
CHCl
3
): 2939, 1587, 1474, 1245, 1130, 993, 825, 731 cm ; HRMS
4.1.14. Compound (3n). Yield¼74% (134 mg); mp¼155e156
(recrystallized from hexanes and EtOAc); IR (CHCl ): 2920, 1481,
þ
1
ESI, M þ1) calcd for C27
400 MHz, CDCl ): 7.71e7.64 (m, 4H), 7.54e7.47 (m, 3H), 7.29e7.19
m, 6H), 6.40 (s, 2H), 3.84 (s, 3H), 3.63 (s, 6H); C NMR (100 MHz,
):
152.65 (2ꢁ), 141.31, 140.80, 140.60, 140.52, 139.63, 136.82,
36.62, 131.06, 129.67 (2ꢁ), 128.86 (2ꢁ), 128.82, 127.99 (2ꢁ), 127.49,
27.17 (2ꢁ), 126.55, 126.18, 107.34 (2ꢁ), 60.93, 55.90 (2ꢁ).
25
H O
3
397.1804, found 397.1810; H NMR
3
ꢂ1
þ
3
d
1446, 1026, 908, 868, 731 cm ; HRMS (ESI, M þ1) calcd for
13
1
C
26 3
H19S 363.1208, found 363.1215; H NMR (400 MHz, CDCl ):
CDCl
1
1
3
d
d
8.13 (br s, 1H), 7.97e7.88 (m, 4H), 7.83 (dd, J¼2.0, 8.4 Hz, 1H), 7.76
(dd, J¼2.0, 8.4 Hz, 1H), 7.55e7.49 (m, 3H), 7.34e7.30 (m, 5H), 7.23
(dd, J¼1.2, 5.2 Hz, 1H), 6.92 (dd, J¼3.6, 5.2 Hz, 1H), 6.81 (dd, J¼1.2,
13
3
3
.6 Hz, 1H); C NMR (100 MHz, CDCl ): d 143.12, 141.09, 140.37,
ꢀ
4
.1.9. Compound (3i). Yield¼66% (156 mg); mp¼169e170
C
139.99, 137.65, 133.72, 133.69, 132.75, 131.36, 129.66 (2ꢁ), 129.59,
128.55, 128.24, 128.07 (2ꢁ), 127.67, 127.13, 127.02, 126.95, 126.68,
126.39, 126.08, 125.86, 125.67, 125.41. Single-crystal X-ray diagram:
crystal of compound 3n was grown by slow diffusion of EtOAc into
(
recrystallized from hexanes and EtOAc); IR (CHCl
3
): 2943, 1586,
ꢂ1
þ
1480, 1242, 1136, 1003, 830, 734 cm ; HRMS (ESI, M þ1) calcd for
C
d
1
H
33 29
O
3
473.2117, found 473.2120; H NMR (400 MHz, CDCl
3
):
7.67e7.59 (m, 4H), 7.54e7.49 (m, 3H), 7.45e7.41 (m, 2H),
2 2
a solution of compound 3n in CH Cl to yield colorless prisms. The

10042
M.-Y. Chang et al. / Tetrahedron 69 (2013) 10036e10044
compound crystallizes in the orthorhombic crystal system, space
(2ꢁ), 127.98, 127.62, 127.40 (2ꢁ), 126.80, 126.36, 126.07, 125.95,
125.85, 125.80 (q, J¼3.7 Hz).
ꢀ
ꢀ
ꢀ
group P c a 21, a¼25.3470(16) A, b¼6.0008(3) A, c¼12.0246(8) A,
ꢀ
3
3
V¼1828.97(19) A , Z¼4, dcalcd¼1.316 g/cm , F(000)¼760, 2
q range
ꢀ
ꢀ
1
.61e26.41 , R indices (all data) R1¼0.0593, wR2¼0.1488.
4.1.20. Compound (3t). Yield¼82% (138 mg); mp¼131e133
recrystallized from hexanes and EtOAc); IR (CHCl
C
(
3
): 2927, 2354,
H O
21
3
): d 7.69e7.63
ꢂ1
þ
4
.1.15. Compound (3o). Yield¼68% (137 mg); colorless oil; IR
1531, 1138, 1022, 794 cm ; HRMS (ESI, M þ1) calcd for C25
ꢂ1
1
(
CHCl
3
): 2937, 1572, 1483, 1145, 1024, 841, 740 cm ; HRMS (ESI,
337.1592, found 337.1597; H NMR (400 MHz, CDCl
þ
1
M þ1) calcd for C25
400 MHz, CDCl ):
H), 7.45 (d, J¼8.0 Hz,1H), 7.34e7.26 (m, 5H), 7.22 (dd, J¼1.2, 5.2 Hz,
H), 6.91 (dd, J¼3.6, 5.2 Hz, 1H), 6.85 (s, 2H), 6.77 (dd, J¼1.2, 3.6 Hz,
H
23
O
3
S 403.1368, found 403.1378; H NMR
(m, 4H), 7.51e7.43 (m, 3H), 7.39e7.34 (m, 1H), 7.29e7.20 (m, 5H),
13
(
3
d
7.73 (d, J¼2.0 Hz, 1H), 7.58 (dd, J¼2.0, 8.0 Hz,
7.10 (d, J¼8.8 Hz, 2H), 6.78 (d, J¼8.8 Hz, 2H), 3.79 (s, 3H); C NMR
(100 MHz, CDCl ): 158.37, 141.70, 140.86, 140.64, 139.99, 139.14,
1
1
1
3
d
133.47, 131.00, 130.90 (2ꢁ), 129.88 (2ꢁ), 129.44, 128.80 (2ꢁ), 127.97
13
3
H), 3.95 (s, 6H), 3.92 (s, 3H); C NMR (100 MHz, CDCl ): d 153.55
(2ꢁ), 127.36, 127.10 (2ꢁ), 126.52, 126.11, 113.39 (2ꢁ), 55.17.
(
2ꢁ), 143.04, 141.02, 140.68, 139.66, 136.38, 133.59, 131.20, 129.61
ꢀ
(
2ꢁ), 129.27, 128.78, 128.05 (2ꢁ), 127.12, 127.02, 126.95, 126.44,
4.1.21. Compound (3u). Yield¼70% (146 mg); mp¼108e110
(recrystallized from hexanes and EtOAc); IR (CHCl
C
1
25.70, 104.49 (2ꢁ), 60.98, 56.27 (2ꢁ).
3
): 2942, 1532,
452, 1133, 1019, 812 cm ; HRMS (ESI, M þ1) calcd for C30
ꢂ1
þ
1
25 2
H O
ꢀ
1
4
.1.16. Compound (3p). Yield¼60% (127 mg); mp¼104e105
C
3
417.1855, found 417.1863; H NMR (400 MHz, CDCl ): d 8.12 (d,
(
recrystallized from hexanes and EtOAc); IR (CHCl
3
): 3042, 2928,
J¼1.6 Hz, 1H), 7.95e7.76 (m, 6H), 7.56e7.47 (m, 3H), 7.21e7.12 (m,
ꢂ1
þ
13
1
621, 1483, 1256, 1168, 937, 873, 755 cm ; HRMS (ESI, M þ1) calcd
3H), 6.86e6.79 (m, 5H), 3.80 (s, 3H), 3.67 (s, 3H); C NMR
1
for C29
H26FO
2
425.1917, found 425.1923; H NMR (400 MHz, CDCl
3
):
3
(100 MHz, CDCl ): d 159.18, 158.44, 143.06, 140.83, 139.83, 139.27,
d
7.62 (dt, J¼2.0, 8.4 Hz, 1H), 7.55e7.49 (m, 3H), 7.35e7.30 (m, 1H),
137.89, 133.71, 133.48, 132.69, 131.09, 130.83 (2ꢁ), 129.49, 128.99,
128.49, 128.43, 127.65, 126.77, 126.42, 125.98, 125.73, 125.45,
122.42, 115.30, 113.45 (2ꢁ), 112.58, 55.21, 55.12.
7
5
.25e7.16 (m, 7H), 6.85 (d, J¼8.4 Hz, 1H), 7.74 (d, J¼8.4 Hz, 1H),
.75e5.65 (m, 1H), 4.82 (dq, J¼1.6, 10.0 Hz, 1H), 4.70 (dq, J¼1.6,
1
1
d
7.2 Hz, 1H), 3.85 (s, 3H), 3.74 (s, 3H), 3.31 (ddt, J¼1.6, 6.0, 14.4 Hz,
13
H), 2.97 (ddt, J¼1.2, 6.0, 14.4 Hz, 1H); C NMR (100 MHz, CDCl
159.89 (d, J¼246.4 Hz), 151.77, 147.29, 140.93, 140.33, 139.61,
36.97, 134.35, 134.20, 132.15, 131.87 (d, J¼3.0 Hz), 130.68 (d,
J¼3.0 Hz), 129.99, 129.48 (2ꢁ), 129.28, 129.01, 128.04 (d, J¼3.8 Hz),
27.70 (2ꢁ), 126.43 (d, J¼3.8 Hz), 124.36, 124.32, 116.13 (d,
J¼22.7 Hz), 114.76, 109.89, 60.60, 55.58, 32.05.
3
):
4.1.22. Compound (3v). Yield¼78% (126 mg); colorless gum; IR
ꢂ1
(CHCl
3
): 2926, 1612, 1512, 1486, 1235, 1145, 837 cm ; HRMS (ESI,
þ
1
1
M þ1) calcd for C24
H
18F 325.1393, found 325.1399; H NMR
7.69e7.64 (m, 4H), 7.49e7.45 (m, 3H),
(400 MHz, CDCl
3
):
d
1
7.39e7.35 (m, 1H), 7.27e7.23 (m, 3H), 7.20e7.17 (m, 2H), 7.15e7.11
13
3
(m, 2H), 6.94e6.90 (m, 2H); C NMR (100 MHz, CDCl ): d 161.77 (d,
J¼244.1 Hz), 141.29, 141.00, 140.52, 140.45, 138.47, 137.06 (d,
J¼3.0 Hz), 131.35 (d, J¼8.4 Hz, 2ꢁ), 130.96, 129.87 (2ꢁ), 129.45,
128.84 (2ꢁ), 128.04 (2ꢁ), 127.49, 127.12 (2ꢁ), 126.70, 126.17, 114.85
(d, J¼21.3 Hz, 2ꢁ).
4
.1.17. Compound (3q). Yield¼68% (148 mg); colorless gum; IR
ꢂ1
1
(
(
(
CHCl
3
): 3054, 2937, 1643, 1464, 1262, 1173, 869, 751 cm ; HRMS
þ
ESI, M þ1) calcd for C30
400 MHz, CDCl ):
7.61 (dt, J¼2.0, 8.0 Hz, 1H), 7.49 (d, J¼2.0 Hz,
H), 7.47 (d, J¼8.0 Hz, 1H), 7.39 (dd, J¼1.6, 7.6 Hz, 1H), 7.34 (dd,
J¼1.6, 7.6 Hz,1H), 7.32 (dd, J¼1.6, 7.6 Hz,1H), 7.22e7.12 (m, 4H), 7.04
29 3
H O 437.2117, found 437.2122; H NMR
3
d
A representative synthetic procedure of compounds 4aeh is as
follows: Potassium t-butoxide (t-BuOK, 140 mg, 1.25 mmol) was
added to a solution of cinnamy sulfone 2a, b, d or crotyl sulfone 2e
(0.5 mmol) in THF (8 mL). A solution of chalcone 1a, b, f, j, l, t or u
(0.5 mmol) in the THF (2 mL) was added to the reaction mixture at
rt. The reaction mixture was stirred at reflux for 3 h. The reaction
mixture was cooled to rt. Water (1 mL) was added to the reaction
1
(
dt, J¼1.2, 7.6 Hz, 1H), 7.00 (d, J¼8.4 Hz, 1H), 6.84 (d, J¼8.4 Hz, 1H),
6
1
3
1
.71 (d, J¼8.4 Hz, 1H), 5.76e5.67 (m, 1H), 4.82 (dq, J¼1.6, 10.0 Hz,
H), 4.72 (dq, J¼1.6, 17.2 Hz, 1H), 3.84 (s, 3H), 3.83 (s, 3H), 3.73 (s,
H), 3.33 (ddt, J¼1.6, 6.0, 14.4 Hz, 1H), 3.01 (ddt, J¼1.2, 6.0, 14.4 Hz,
13
ꢀ
H); C NMR (100 MHz, CDCl
3
):
d
156.57, 151.65, 147.25, 141.27,
mixture at 0 C. The solvent was concentrated under reduced
1
1
1
39.50, 139.02, 137.14, 136.97, 134.70, 132.45, 132.25, 130.85, 130.12,
29.56, 129.53 (2ꢁ), 128.64, 128.52, 127.63 (2ꢁ), 126.48, 126.23,
20.85, 114.69, 111.22, 109.82, 60.59, 55.57, 55.56, 32.01.
pressure. The residue was diluted with water (10 mL) and the
mixture was extracted with EtOAc (3ꢁ20 mL). The combined or-
ganic layers were washed with brine, dried, filtered, and evapo-
rated to afford crude product. Purification on silica gel (hexanes/
EtOAc¼10/1e6/1) afforded compounds 4aeh.
4
.1.18. Compound (3r). Yield¼73% (147 mg); colorless gum; IR
ꢂ1
1
(
(
(
CHCl
3
): 2920, 1617, 1325, 1168, 1126, 1095, 850, 835 cm ; HRMS
þ
ESI, M þ1) calcd for C26
400 MHz, CDCl ):
7.78 (d, J¼8.4 Hz, 2H), 7.72 (d, J¼8.0 Hz, 2H),
.62e7.62 (m, 2H), 7.52 (d, J¼8.0 Hz, 1H), 7.29e7.23 (m, 3H),
.21e7.18 (m, 2H), 7.11 (d, J¼8.8 Hz, 2H), 6.79 (d, J¼8.8 Hz, 2H), 3.80
s, 3H); 13C NMR (100 MHz, CDCl
): 158.54, 144.19, 144.18, 141.01,
40.86, 140.42, 138.84, 133.49, 131.33, 130.90 (2ꢁ), 129.78 (2ꢁ),
29.45, 128.01 (2ꢁ), 127.36 (2ꢁ), 126.78 (2ꢁ), 126.65, 125.87, 125.76
q, J¼3.8 Hz), 113.50 (2ꢁ), 55.19.
H
20
F
3
O 405.1466, found 405.1475; H NMR
4.1.23. Compound (4a). Yield¼70% (139 mg); colorless gum; IR
3
d
(CHCl
3
): 3152, 2989, 1731, 1592, 1485, 1223, 1183, 1148, 1091, 1016,
þ
7
7
(
1
1
(
957, 822; HRMS (ESI, M þ1) calcd for C26
H
23
O
4
399.1596, found
1
3
399.1592; H NMR (400 MHz, CDCl ): d
8.06 (d, J¼8.8 Hz, 2H),
3
d
7.28e7.16 (m, 5H), 6.99 (d, J¼8.8 Hz, 2H), 6.81e6.76 (m, 3H), 6.63 (d,
J¼15.6 Hz,1H), 5.96 (d, J¼1.6 Hz,1H), 5.95 (d, J¼1.6 Hz,1H), 5.72 (dd,
J¼10.0, 15.6 Hz, 1H), 3.89 (s, 3H), 3.24 (dd, J¼5.2, 9.2 Hz, 1H), 3.16
13
(dd, J¼4.4, 5.2 Hz, 1H), 2.73 (dt, J¼4.4, 9.2 Hz, 1H); C NMR
(100 MHz, CDCl
3
):
d
196.10, 163.54, 147.66, 146.46 (2ꢁ), 137.04,
ꢀ
4
.1.19. Compound (3s). Yield¼70% (148 mg); mp¼115e116
C
132.02,130.72,130.37 (2ꢁ),128.49 (2ꢁ),127.20,126.89,125.91 (2ꢁ),
(
recrystallized from hexanes and EtOAc); IR (CHCl
3
): 1632, 1475,
122.25,113.83 (2ꢁ),109.69,108.16,101.01, 55.48, 35.51, 34.32, 32.44.
ꢂ1
þ
1258, 1162, 945, 875, 750 cm ; HRMS (ESI, M þ1) calcd for
C
d
1
H
29 20
F
3
425.1517, found 425.1524; H NMR (400 MHz, CDCl
3
):
4.1.24. Compound (4b). Yield¼65% (131 mg); colorless gum; IR
7.84e7.79 (m, 8H), 7.74 (d, J¼8.0 Hz, 2H), 7.71 (dd, J¼2.4, 8.0 Hz,
3
(CHCl ): 3158, 3004,1738,1604,1457,1232,1189,1123,1112, 960, 856;
þ
1
1
H), 7.65 (d, J¼8.4 Hz, 1H), 7.60 (d, J¼8.0 Hz, 1H), 7.49e7.47 (m, 2H),
HRMS (ESI, M þ1) calcd for C29
25 2
H O 405.1855, found 405.1862; H
13
7.24e7.21 (m, 3H), 7.19 (dd, J¼2.0, 8.4 Hz, 1H); C NMR (100 MHz,
NMR (400 MHz, CDCl ):
7.79 (s, 1H), 7.52e7.45 (m, 3H), 7.23e7.12 (m, 5H), 7.02 (d, J¼8.8 Hz,
2H), 6.68 (d, J¼16.0 Hz, 1H), 5.74 (dd, J¼9.6, 16.0 Hz, 1H), 3.90 (s, 3H),
3
d
8.13 (d, J¼8.8 Hz, 2H), 7.86e7.81 (m, 3H),
CDCl
3
):
d
144.10, 141.10, 140.71, 140.64, 138.95, 138.90, 133.37,
132.16, 131.40, 130.19, 129.87, 129.83 (4ꢁ), 128.43, 128.21, 128.08

M.-Y. Chang et al. / Tetrahedron 69 (2013) 10036e10044
10043
3
9
.50 (dd, J¼5.6, 9.2 Hz, 1H), 3.39 (t, J¼4.4 Hz, 1H), 2.86 (dt, J¼4.4,
.2 Hz, 1H); 13C NMR (100 MHz, CDCl
): 196.16, 163.58, 136.95,
J¼15.6 Hz,1H), 5.91 (d, J¼1.2 Hz,1H), 5.89 (d, J¼1.2 Hz,1H), 5.54 (dd,
J¼9.6, 15.6 Hz, 1H), 3.33 (dd, J¼5.2, 9.2 Hz, 1H), 3.27 (dd, J¼4.4,
3
d
13
1
1
1
34.32, 133.32, 132.43, 132.22, 130.78, 130.44 (2ꢁ), 128.45 (2ꢁ),
28.09, 127.68 (2ꢁ),127.60,127.49,127.19,126.77,126.19,125.88 (2ꢁ),
25.73, 113.86 (2ꢁ), 55.50, 35.69, 34.64, 32.31.
5.2 Hz, 1H), 2.78 (dt, J¼4.4, 9.2 Hz, 1H); C NMR (100 MHz, CDCl
3
):
d
197.91, 147.91, 146.95, 137.79, 136.49, 133.02, 131.88, 131.56, 129.13
(2ꢁ), 128.67 (2ꢁ), 128.46 (2ꢁ), 128.12 (2ꢁ), 126.92, 124.76, 120.57,
08.24, 105.23, 100.98, 35.95, 34.98, 32.64.
1
4
.1.25. Compound (4c). Yield¼73% (126 mg); colorless gum; IR
(
(
(
7
(
CHCl ): 3147, 2984, 1757, 1450, 1221, 1176, 1115, 943, 823; HRMS
3
4.1.30. Compound (4h). Yield¼56% (73 mg); colorless oil; IR
þ
1
ꢂ1
ESI, M þ1) calcd for C23
400 MHz, CDCl ):
7.97 (d, J¼8.4 Hz, 2H), 7.32 (d, J¼8.0 Hz, 2H),
.28e7.18 (m, 6H), 7.00e6.98 (m, 2H), 6.68 (d, J¼16.0 Hz, 1H), 5.94
H
21SO 345.1313, found 345.1320; H NMR
(CHCl
3
): 2943, 1754, 1655, 1428, 1236, 1135, 873 cm ; HRMS (ESI,
þ
1
3
d
M þ1) calcd for C19
H
19O 263.1436, found 263.1442; H NMR
8.09e8.07 (m, 2H), 7.54e7.52 (m, 3H),
(400 MHz, CDCl
3
):
d
dd, J¼8.8, 16.0 Hz, 1H), 3.36 (dd, J¼5.2, 8.8 Hz, 1H), 3.26 (dd, J¼4.8,
7.35e7.31 (m, 5H), 5.79e5.70 (m, 2/3H), 5.62e5.54 (m, 1/3H),
5.06e4.96 (m, 1H), 3.29e2.17 (m, 2H), 2.86 (dt, J¼4.4, 9.6 Hz, 1/3H),
2.66 (dt, J¼4.8, 9.6 Hz, 2/3H), 1.76 (dd, J¼2.0, 6.8 Hz, 1H), 1.63 (dd,
J¼2.0, 6.8 Hz, 2H).
13
5
.2 Hz, 1H), 2.82 (dt, J¼4.8, 8.8 Hz, 1H), 2.45 (s, 3H); C NMR
): 196.63, 144.00, 140.23, 136.97, 135.03, 132.66,
29.36 (2ꢁ), 128.51 (2ꢁ), 128.28 (2ꢁ),127.33, 126.89, 126.32,126.14,
(
100 MHz, CDCl
3
d
1
125.99 (2ꢁ), 124.31, 35.75, 34.64, 29.47, 21.64.
Acknowledgements
ꢀ
C
4
.1.26. Compound (4d). Yield¼80% (134 mg); mp¼135e136
(
recrystallized from hexanes and EtOAc); IR (CHCl
3
): 3134, 2965,
The authors would like to thank the National Science Council of
the Republic of China for its financial support (NSC 102-2113-M-
037-005-MY2).
þ
1
3
742, 1468, 1245, 943; HRMS (ESI, M þ1) calcd for C23
27 2
H O
1
3
35.2011, found 335.2016; H NMR (400 MHz, CDCl ): d 7.27e7.15
(
m, 7H), 6.87 (d, J¼8.8 Hz, 2H), 6.59 (d, J¼15.6 Hz, 1H), 5.62 (dd,
J¼10.0, 15.6 Hz, 1H), 3.82 (s, 3H), 3.00 (dd, J¼4.8, 9.2 Hz, 1H), 2.71
Supplementary data
13
(
dd, J¼4.4, 4.8 Hz, 1H), 2.52 (dt, J¼4.4, 9.2 Hz, 1H), 1.29 (s, 9H);
NMR (100 MHz, CDCl ):
28.61, 128.45 (2ꢁ), 127.11, 127.12, 125.83 (2ꢁ), 113.81 (2ꢁ), 55.22,
C
Scanned photocopies of 1H and 13C NMR spectral data were
supported. Supplementary data related to this article can be found
at http://dx.doi.org/10.1016/j.tet.2013.09.060.
3
d
212.70, 158.41, 137.09, 131.55, 130.15 (2ꢁ),
1
4
4.09, 35.03, 33.76, 31.50, 26.22 (3ꢁ). Single-crystal X-ray diagram:
crystal of compound 4d was grown by slow diffusion of EtOAc into
a solution of compound 4d in CH Cl to yield colorless prisms. The
compound crystallizes in the monoclinic crystal system, space
2
2
References and notes
ꢀ
ꢀ
ꢀ
group P 1 21/c 1, a¼10.1827(10) A, b¼55.170(4) A, c¼33.557(3) A,
1. (a) Saito, S.; Yamamoto, Y. Chem. Rev. 2000, 100, 2901; (b) Maitlis, P. M. Acc.
Chem. Res. 1976, 9, 93.
ꢀ
3
3
V¼1882.8(3) A , Z¼4, dcalcd¼1.180 g/cm , F(000)¼720, 2
q range
2
. (a) Liu, J.-K. Chem. Rev. 2006, 106, 2209; (b) Mullen, K.; Wegner, G. Electronic
Materials: the Oligomer Approach; Wiley-VCH: Weinhein, Germany, 1988; (c)
Chen, B.; Baumeister, U.; Pelzl, G.; Das, M. K.; Zeng, X.; Ungar, G.; Tschierske, C. J.
Am. Chem. Soc. 2005, 127, 16578; (d) Wright, R. S. Tetrahedron Lett. 2003, 44,
7129; (e) Udayakumar, B. S.; Schuster, G. B. J. Org. Chem. 1992, 57, 348.
. (a)Ohkanda,J.;Lockman,J. W.;Kothare,M. A.;Qian,Y.;Blaskovich, M. A.;Sebti, S. M.;
Hamilton, A. D. J. Med. Chem. 2002, 45,177; (b) Roberti, M.; Pizzirani, D.; Recanatini,
M.;Simoni, D.; Grimaudo, S.;Di Cristina, A.; Abbadessa, V.;Gebbia, N.;Tolomeo, M. J.
Med. Chem. 2006, 49, 3012; (c) Lin, J. M.; Gowda, A. S. P.; Sharma, A. K.; Amin, S.
Bioorg. Med. Chem. 2012, 20, 3202; (d) Guo, H.; Hu, H.; Liu, S.; Liu, X.; Zhou, Y.; Che, Y.
J. Nat. Prod. 2007, 70, 1519; (e) Zhang, C.; Ondeyka, J. G.; Herath, K. B.; Guan, Z.;
Collado, J.; Pelaez, F.;Leavitt, P. S.; Gurnett, A.; Nare, B.; Liberator, P.; Singh, S. B. J. Nat.
Prod. 2006, 69, 710.
ꢀ
1
.22e26.40 , R indices (all data) R1¼0.0754, wR2¼0.1749.
4
.1.27. Compound (4e). Yield¼62% (110 mg); colorless gum; IR
ꢂ1
(
(
(
CHCl
3
): 2945, 1753, 1632, 1527, 1469, 1212, 1133, 865 cm ; HRMS
3
þ
1
ESI, M þ1) calcd for C25
400 MHz, CDCl ):
8.09 (d, J¼8.8 Hz, 2H), 7.63e7.58 (m, 1H),
.54e7.50 (m, 2H), 7.38e7.34 (m, 4H), 7.31e7.26 (m, 1H), 7.15 (d,
23 2
H O 355.1698, found 355.1708; H NMR
3
d
7
J¼8.8 Hz, 2H), 6.79 (d, J¼8.4 Hz, 2H), 6.60 (d, J¼16.0 Hz, 1H), 5.60
(
(
(
1
(
dd, J¼9.6,16.0 Hz,1H), 3.78 (s, 3H), 3.36 (dd, J¼5.2, 9.2 Hz,1H), 3.30
13
dd, J¼4.4, 5.2 Hz, 1H), 2.82 (dt, J¼4.4, 9.2 Hz, 1H); C NMR
100 MHz, CDCl ): 197.95, 158.96, 137.79, 136.57, 132.97, 131.72,
29.85, 129.14 (2ꢁ), 128.63 (2ꢁ), 128.40 (2ꢁ), 128.09 (2ꢁ), 127.06
2ꢁ), 126.83, 124.23, 113.90 (2ꢁ), 55.21, 36.14, 34.93, 32.67.
4
. (a) Perato, S.; Voisin-Chiret, A. S.; Santos, J. S. O.; Legay, R.; Oulyadi, H.; Rault, S.
Tetrahedron 2012, 68, 1910; (b) Guillen, E.; Hierrezuelo, J.; Martínez-Mallorquin,
R.; Lopez-Romero, J. M.; Rico, R. Tetrahedron 2011, 67, 2555; (c) De Giorgi, M.;
Voisin-Chiret, A. S.; Santos, J. S. O.; Corbo, F.; Franchini, C.; Rault, S. Tetrahedron
3
d
2011, 67, 6145; (d) Zhang, X.; Xie, W.; Chen, W. Tetrahedron 2010, 66, 1188; (e)
Voisin-Chiret, A. S.; Muraglia, M.; Burzicki, G.; Perato, S.; Corbo, F.; Santos, J. S. O.;
Franchini, C.; Rault, S. Tetrahedron 2010, 66, 8000; (f) King, B. T.; Kroulik, J.;
Robertson, C. R.; Rempala, P.; Hilton, C. L.; Korinek, J. D.; Gortari, L. M. J. Org. Chem.
4
.1.28. Compound (4f). Yield¼76% (165 mg); colorless gum; IR
ꢂ1
1
(
(
(
CHCl
3
): 3034, 2923, 1749, 1638, 1434, 1221, 1132, 848 cm ; HRMS
2
2
007, 72, 2279; (g) Goto, H.; Furusho, Y.; Miwa, K.; Yashima, E. J. Am. Chem. Soc.
009, 131, 4710; (h) Ormsby, J. L.; Black, T. D.; Hilton, C. L.; Bharat; King, B. T.
þ
ESI, M þ1) calcd for C30
27 3
H O 435.1960, found 435.1972; H NMR
400 MHz, CDCl ):
3
d
8.62 (s, 1H), 8.13 (d, J¼8.8 Hz, 1H), 8.01 (d,
Tetrahedron 2008, 64, 11370; (i) Mitchell, P. S. R.; Sengul, I. F.; Kandemir, H.;
Nugent, S. J.; Chen, R.; Bowyer, P. K.; Kumar, N.; Black, D. S. Tetrahedron 2012, 68,
J¼7.6 Hz,1H), 7.94 (d, J¼8.8 Hz,1H), 7.90 (d, J¼8.0 Hz,1H), 7.64e7.55
8163; (j) Kikuchi, H.; Matsuo, Y.; Katou, Y.; Kubohara, Y.; Oshima, Y. Tetrahedron
(
m, 2H), 7.30 (t, J¼8.0 Hz, 1H), 7.18 (d, J¼8.8 Hz, 2H), 6.99 (d,
2012, 68, 8884; (k) Dohi, T.; Kamitanaka, T.; Watanabe, S.; Hu, Y.; Washimi, N.;
J¼7.6 Hz, 1H), 6.95 (s, 1H), 6.85 (dd, J¼2.0, 8.4 Hz, 1H), 6.81 (d,
Kita, Y. Chem.dEur. J. 2012, 18, 13614.
. (a) Hassan, J.; Sevignon, M.; Gozzi, C.; Schulz, E.; Lemaire, M. Chem. Rev. 2002,
5
J¼8.8 Hz, 2H), 6.63 (d, J¼15.6 Hz, 1H), 5.70 (ddd, J¼0.8, 9.6, 15.6 Hz,
102, 1359; (b) Schroter, S.; Stock, C.; Bach, T. Tetrahedron 2005, 61, 2245; (c)
1
H), 3.82 (s, 3H), 3.78 (s, 3H), 3.45 (dd, J¼5.2, 9.2 Hz, 1H), 3.41 (dd,
13
Schnurch, M.; Flasik, R.; Khan, A. F.; Spina, M.; Mihovilovic, M. D.; Stanetty, P.
Eur. J. Org. Chem. 2006, 3283; (d) Wang, R.; Manabe, K. Synthesis 2009, 1405.
. (a) Varela, J. A.; Saa, C. Chem. Rev. 2003, 103, 3787; (b) Grotjahn, D. B. Transition
Metal Alkyne Complexes: Transition Metal-catalyzed Cyclotrimerization. In
Comprehensive Organometallic Chemistry II; Abel, E. W., Stone, F. G. A., Wilkin-
son, G., Eds.; Hegedus, L. S., Vol. Ed.; Pergamon: Oxford, UK, 1995; Vol. 12, p 741.
(c) Hilt, G.; Vogler, T.; Hess, W.; Galbiati, F. Chem. Commun. 2005, 1474; (d) Xu,
L.; Yu, R.; Wang, Y.; Chen, J.; Yang, Z. J. Org. Chem. 2013, 78, 5744; (e) Ozelov, O.
V.; Patrick, B. O.; Ladipo, F. T. J. Am. Chem. Soc. 2000, 122, 6423; (f) Cicero, D.;
Lembo, A.; Leoni, A.; Tagliatesta, P. New J. Chem. 2009, 33, 2162; (g) Cadierno, V.;
Garcia-Garrido, S. E.; Gimeno, J. J. Am. Chem. Soc. 2006, 128, 15094; (h) Sugihara,
T.; Wakabayashi, A.; Nagai, Y.; Takao, H.; Imagawa, H.; Nishizawa, M. Chem.
Commun. 2002, 576; (i) Bu, X.; Zhang, Z.; Zhou, X. Organometallics 2010, 29,
J¼4.4, 5.2 Hz, 1H), 2.87 (dt, J¼4.4, 9.2 Hz, 1H); C NMR (100 MHz,
CDCl ): 197.72, 159.60, 158.95, 138.23, 135.52, 135.07, 132.53,
31.78, 129.87, 129.68, 129.58, 129.39, 128.50, 128.40, 127.75, 127.08
6
3
d
1
(
5
2ꢁ), 126.77, 124.27, 123.93, 121.42, 115.08, 113.90 (2ꢁ), 112.15,
5.20 (2ꢁ), 36.33, 34.98, 32.76.
4
.1.29. Compound (4g). Yield¼71% (131 mg); colorless gum; IR
ꢂ1
(
CHCl
3
): 3253, 2945, 1755, 1439, 1236, 1154, 850 cm ; HRMS (ESI,
þ
1
M þ1) calcd for C25
H
21
O
3
369.1491, found 369.1498; H NMR
8.07 (d, J¼8.4 Hz, 2H), 7.62e7.58 (m, 1H), 7.52
d, J¼7.6 Hz, 2H), 7.37e7.25 (m, 5H), 6.70e6.64 (m, 3H), 6.55 (d,
(
(
3
400 MHz, CDCl ): d
3530; (j) Liu, Y.; Yan, X.; Yang, N.; Xi, C. Catal. Commun. 2011, 12, 489; (k) Zhao,
F.; Zhang, Y.-F.; Wen, J.; Yu, D.-G.; Wei, J.-B.; Xi, Z.; Shi, Z.-J. Org. Lett. 2013, 15,

10044
M.-Y. Chang et al. / Tetrahedron 69 (2013) 10036e10044
3
230; (l) Yu, D.-G.; Yu, M.; Guan, B.-T.; Li, B.-J.; Zheng, Y.; Wu, Z.-H.; Shi, Z.-J.
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giero, P. L.; Tang, Y. Org. Lett. 2004, 6, 3373; (d) Vincze, Z.; Nemes, P. Tetrahedron
2013, 69, 6269.
7
2
2
010, 51, 2810; (b) Hassan, Z.; Hussain, M.; Villinger, A.; Langer, P. Tetrahedron
012, 68, 6305.
14. (a) Beaudry, C. M.; Trauner, D. Org. Lett. 2002, 4, 2221; (b) Parker, K. A.; Wang, Z.
Org. Lett. 2006, 8, 3553; (c) Webster, R.; Gaspar, B.; Mayer, P.; Trauner, D. Org.
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8
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0. (a) Chang, M.-Y.; Wu, M.-H. Tetrahedron 2012, 68, 9616; (b) Chang, M.-Y.; Tai, H.-Y.;
1
Chen, Y.-L.; Hsu, R.-T. Tetrahedron 2012, 68, 7941; (c) Chang, M.-Y.; Wu, M.-H.; Tai,
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1
1. (a) Shu, Z.-C.; Zhu, J.-B.; Liao, S.; Sun., X.-L.; Tang, Y. Tetrahedron 2013, 69, 284;
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2. (a) Blakemore, P. R. J. Chem. Soc., Perkin Trans. 1 2002, 2563; (b) Kumar, A.;
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17. CCDC 947878 (3g), 948282 (3n), and 947225 (4d) contains the supplementary
crystallographic data for this paper. This data can be obtained free of charge via
www.ccdc.cam.ac.uk/conts/retrieving.html (or from the CCDC, 12 Union Road,
Cambridge CB2 1EZ, UK; fax: 44-1223-336033; e-mail: deposit@ccdc.cam.ac.
uk).
18. (a) Martel, J.; Huynh, C. Bull. Soc. Chem. Fr. 1967, 2, 985; (b) Campbell, R. V. M.;
Crombie, L.; Findley, D. A. R.; King, R. W.; Pattenden, G.; Whiting, D. A. J. Chem.
Soc., Perkin Trans. 1 1975, 897; (c) Krief, A.; De Vosa, M. J. Tetrahedron Lett. 1985,
26, 6115.
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